This invention relates to cable actuated bicycle brakes and is an improvement over the variable leverage caliper brake assembly disclosed in U.S. Pat. No. 3,870,127 to Wilson et al.
The brake assembly disclosed in the aforementioned patent is operative to engage a bicycle wheel rim with brake pads carried on caliper elements, in two stages. During an initial stage, the brake pad attached to the pivoted caliper and the brake pad slidably mounted on the other of the calipers are displaced relative to each other for take-up movement at a low mechanical advantage. In response to brake contact, the slidable caliper is locked against further movement relative to the pivoted caliper resulting in continued braking force being applied at a high mechanical advantage.
The foregoing brake assembly required excessive cable motion during the initial take-up stage and consequently a special hand lever actuator for the Bowden wire cable assembly. Also, cable routing was relatively inconvenient and relatively large and bulky parts were required to obtain the requisite braking pressures. It is therefore an important object of the present invention to provide a variable leverage type of caliper brake assembly having greater design flexibility with respect to braking pressures, cable routing and adjustability. Also, an additional object is to enable use of a standard lever type actuator for the brake assembly.